Lapping machine



' r 1,635,469 y 12, 1927. A ERICSSON I LAPPI NG MACHINE Filed Nov. 5. 1924 4 Sheets-Sheet l 6H0: um S July 1251927" Ayzllcssom LAPPING MACHINE Filed Nov. 3, 1924 4 Sheets-Sheet 2 Uen-fm & m N

\ (momma 4 July 12 1927. l,5,469

ERICSSON LAPFING MACHINE Filed Nov.'3. 1 24 4 Sheets-Sheet 3 July 12, 1927.

A. EmcssoN 'LAPPING MACHINE Filed Nov. 5, 1924 Q 4 Sheets-Sheet 4 Passed July 12,1927.

'ABVH) EBICSSOH, OF CHICAGO, ILLINOIS, ASSIGNOR T UNION SPECIAL EA COMPANY, 01' CHICAGO, ILLINOIS, A COBPOTION 0F 'OIB.

mrnm ennui.

Application filed Iovembcr 8, 1984. Serial No. 747,658.

This invention relates to lapping machines for ball joints, and the like, wherein it is desired to impart to one of the two members of the joint a prescribed wabbling movement to insure the more perfect fitting and operation of the joint.

One of the objects of the present invention resides in providing a device for imparting a prescribed wabbli'ng movement to one of l the two members to be lapped, which device is constructed so as to prevent objectionable vibrational motions tending to modify the desired movement.

Yet a further feature of the invention resides in providing a rugged, compactly arranged device of the character described.

Another object of-the invention resides in the arrangement of the rotatable bearin for firmly supportin the rotaryinclined carrying one of t e members to be lapped.

An additional object resides in the construction of the collet or chuck for holding the member to be lapped, which collet is arranged axially of the inclined shaft and is I operable from the rear or accessible end of the shaft.

A further feature of the. invention resides in the novel arrangement of the holder for the other member to be lapped whereby it may be held firmly in lapping position or swung to a position for withdrawing the member from its holder.

Yet a further feature of the invention lies in the arrangement of the driving mechanism whereby one or more lapping devices may be driven at will from a common power shaft.

These and other objects will be ap arent? from a perusal of the followin spec cation when taken in connection wit the accompanying drawings, wherein- Figure 1 is a sectional view of one end of the machine showing one complete lapping unitand its geared connection to the longitudinal power shaft;

Fig. 2 is a view taken on line 2-2 of F ig. 3;

ig. 3 is an end view of Figure 1, and

Fig. 4 is the reverse end view of Figure 1. Referrin now to the drawings in detail, the device is preferably arranged as a gang machine for simultaneously lapping any number of joints, each unit beinge driven from a common power shaft and ing in- II dependently operable. Further, the invenaft tion is illustrated as a device for la ping ball oints of sewing machines, but obv1ously 1t 1s of general application. The device comprisesa relativelylong castmg formed at intervals along its length with upright bearings to support the rotating shafts of each unit. Inasmuch as the separate units are similar, the descri tion of one w1llsuiiice. For instance, in 1 1 the casting is shown as formed with a re atively broad base 1 having an upturned flange 2 to catch the oil drippings. The base is pro vided with upstanding walls 3 and 4 sup porting the bearings 5 and 6 for the power shaft 7, which is provided with the driving pulley 8 on its outer end. As before mentioned, shaft- 7 extends the entire length of the base.

Arranged preferably immediately above the power shaft 7 and preferably axially ar allel thereto is a rotatable bearing 9. his bearing has one end rotatively mounted in the upper portion 10 of the u standing wall 4 and to this end is provided with a bear- The opposite end of the rotatablebearin 9 is provided with an axially arrange bore to receive a short fixed shaft 12 mounted in an end cover 13 attached by suitable screws 14 to the upper housing 15 of the casting. This rotata le bearing 9 carries the inclined shaft 16 supportin one of the members to be lapped. To t is end bearing 9 is formed with a bore disposed at an acute an 'le with respect to the axis of rotation of t e bearing1 and shaft 16 is rotatively mounted in t is b'oreb means of the bearing sleeves 17 and 18. haft 16 in turn is provided with an axial bore, which bore is enlarged at the inner end as at 19 to house the collet or chuck 20 consisti of a hollow sleeve having s ring grippin ngers 21. The exterior sur ace of these gers is preferably curved in order to protect the ands of the operator. One of the members of the ball joint adapted to be lapped, in the present instance the ball member 22, provided with the threaded shank member 23, is seated in a countersunk bore in this chuck 21 and is held in desired position therein by means of a stop pin 24 which has threaded m5 enga ement with the inner wall of the hollow 0 uck sleeve 20. Manifestly, by adjusting the stop pin 24 the correct position of the member 23 is secured. The chuck is drawn into gripping engagement with the no.

ing 11.

member 23 by means of the wedge shaped faces 25 at the inner end of shaft 16 engaging the chuck fingers 21 and by means of a draw pin 26, the inner end of which is threaded to engage the chuck sleeve 20.

Means is rovided for rotati-n the hearing 9 from t e power shaft and or rotating the inclined shaft 16 in the rotary bearing 9. In the preferred form, the power shaft 7 is provided with a spline 27 on which slides a member 28 of a clutch. This clutch member accordingly is formed with a sleeve 29 on which threads a nut 30 adapted to confine lugs 31 in position between a shoulder on the clutch and a ball bearing 32. Lugs 31 are carried by the forks of a shifter lever 33 mounted on the end of a pivoted shaft 34 adapted to be oscillated through a lever 35 which lever is formed on its upper end with a detent 36, spring-pressed to engage in a recess *37 (see Fig. 4). In this manner, the clutch can be locked in either position. A s ring 38 housed in a counter bore 39 coils a cut shaft 7 and presses the clutch 28 normally into engagement with a cooperative clutch member 40 provided on its lperiphery with gear teeth 41 which mesh wit teeth 42 formed on the periphery of the inner portion ,of the rotary bearing 9. The clutch member 40 carr 1n the gear teeth 41 is mounted on a us ing 40. This clutch member is freely mounted on the bushing and is held from endwise movement on the shaft 7 by collars 40 and 40", Which' are secured to the shaft by suitable set screws. This clutch member which is geared to the bearing 9, is connected to the shaft 7 bv means of the clutch member 28, which clutch member is splined to the shaft and movable longitudinally on the shaft into frictional gripping connection with this clutch member 40. Thus this hearing is rotated in its bearing 11. In order to rotate the inclined shaft 16 from the rotation of bearing 9, shaft 16 is provided on its rear end with a pinion 43 meshing with a pinion 44 fixed on the stationary shaft 12. So that as the bearing 9 rotates about shaft 12, pinion 43 will revolve around pinion 44 which is stationary and Willbe positivel rotated to turn the inclined shaft 16. T is combined rotation of bearing 9 and inclined shaft 16 pro-- duces the desired wabbling movement of the member 23 carried on the chuck 21.

- The rotatable member 9 at the opposite side of the axis of the fixed shaft 12 from the shaft 16 and gear wheel 43 is rovided with a weighted. member 43", whic counterbalances the parts so that this member 9 will rotate with little or no vibration. The rotatable member 9 is in art supported by this fixed shaft 12 and 1n part supported b the bushing 11 in the frame of the mac inc, and the shaft 16 extends through a portion of the member 9 which is located in the bushing 11. This greatly facilitates the positioning of the parts so that the axis of the shaft 16 intersects the axis of the stationary shaft 12 and the axis of rotation of the member 9 at the center of the ball which is being lapped.

It Wlll be noticed that due to the stationary bearing 11, the bearing 9 is iven a firm. rotation so that the inclined shaft 16 carried thereby is also firmly held and the consequent rotation of shaft 16 is free from vibrational strains and movements occasioned by the lapping operation. This is most im ortant-this construction whereby the chuc 21 is firmly supported during its wabbling movement inasmuch as the lapping of the members must be precise.

The other cooperative member to be lap ed is firmly held in a bracket or work ho er in proper position with respect to the member 23. To this end, the casting 1 is formed with a slotted arm 45 in which is adjustably mounted, asby means of a nut 46.

the stud 47. The other end of the stud is similarly mounted. Stud 47 has pivotally mounted thereon the work supporting arm 48 having a recess 49, in which is mounted the strap or shell 50 which is the other member to be lapped. This shell 50 is held from swinging outwardly by the set screws 51 and lock nuts 52 located at the outer face of the work supporting arm. Work supporting arm 48 is supported on a stud 53 which bears a ainst the lower portion of the castin 1.

or the purpose of removing the work, that is, the shell 50, the work supporting arm 48 may be swung upwardly. A cover 53 is pivoted at 54 to the casting. This cover houses the work supportin members and excludes dirt and dust from the lapping members during their relative movement. This cover 53 may be lifted by a pin 55 and is held in a predetermined lifted position by the stop 56.

It W111 be noted that in the machine, as above described, all working parts are enclosed and that each individual machine is driven from the power shaft by means of a clutch. It will also be noted that the ideal lapping osition of the ball 22 and strap 50 is such t at the center of the ball coincides with the axes of both the rotating bearing 9 and the rotating inclined shaft 16. The strap 50 of course, being held from rotation during the wabbling movement of the ball. The arrangement herein produces a more accurately lapped joint in a much shorter time than any known previous arrangement.

The draw in 26 is provided with a rectangular hear 26, to whicha wrench mav be applied through an opening 26 in the cad ing 13. This makes very ready means for adjusting the draw pin 26 for moving the chuck sleeve 20 to cause the chuck fingers to grip the shank of the member carrying the hall which is to be lapped. The device described above is particularly useful in connection with the lapping of ball and socket joints. The shankof the ball member is inserted in the chuck 20, and the jaws 21- of the chuck tightenedon to the shank through the aid of the draw pin 26; This firmly clamps the ball member. The socket member of the joint is placed in the recess 49 after the manner indicated in Figure 2, and clamped therein by the bolts 51. Of course,

f the socket is placed'on the ball. It will be noted that the axis of the shaft 16 and the axis of the stationary shaft 12 on which the bearing 'member) Y rotates intersect each other substantially at the center of the ball which is to be lapped. After the parts bar e been placed in the machine after the manner stated, the ball and socket are flooded wlth a mixture of oil and a grinding compound When the parts have been sufliciently ground or lapped by this first compound, they are taken apart, washed, and placed in another machine of the same type and lapped as before with the final compound. They are then taken apart and washed again, and finally lapped in still another machine, or in the same machine, without any compound at all. This results in a bu'rnishing of the surfaces of the ball and socket.

It is obvious that minor changesin the details of construction and the arran ment of the parts may be made without eparting from the spirit of the invention as set forth in-the appended claims.

Having thus described the invention, what- I claim as new and desire to secure by Letters-Patent, is

1. In a machine for lappin ball and socket joints. the combination 0 a supportin frame,;a rotatable member mounted on said frame, means for rotating said member, a rotatable shaft carried by said member and disposed at an acute au io to the longitudinal axis of said rotatable member, means whereby said rotatable member as it rotates, rotates said shaft, said rotatable member and said shaft being so disposed relative to each other that their axes intersect each other at the center of the ball bein lapped.

2. In a machine for lappin all and socket joints, the combination 0% a supporting frame, a rotatable member carried by said frame, means for rotating said member including a clutch, a shaft carried by said member and dispose at an acute an le to the axis of-said member, whereby as sai member is rotated, said shaft will be carried bodily therewith means whereby the rotation of said member imparts rotations to said shaft, means carried by said shaft for supportin the ball to be lapped, and means carrie by the frame for supporting the socket in engagement with sa-i ball.

3. In a machine for lapping ball and socket joints, the combination of a supporting frame, a rotatable member carried by said frame, means for rotating said member including aclutch, a shaft carried by said member and dispose at an acute an le to the axis of said member, whereby as sai member is rotated, said. shaft will be carried bodily therewith, means whereby the rotation of said member imparts rotations to said shaft, means carried by said shaft for supporting the ball tobe lapped, and means carried by the frame for supporting the socket in engagement with said ball, the axis of said shaft and the axis of said rotatable member being so disposed as to intersect at the center of the ball being lapped.

4. In a machine for lapping ball and socketjoints, the combination of a supporting frame, a fixed shaft carried thereby, a rotatable member mounted at one end on said fixed shaft and rotatable thereon and mounted at its other end in a bushing which surrounds said rotatable member, means for rotating said member, an inclined shaft mounted in said rotatable member and?" extending through said bushing to a point beyond the end of said rotatable member, means for mounting the ball onthe end of said shaft, means whereby said rotatable member rotates said shaft, means carried by the frame for supporting the socket which is to be lapped with said ball, said inclined shaft and said rotatable member being so disposed relative to each other that their axes intersect in the center of the ball bein lapped.

5. In a mac ine for lapping ball and socket joints, the combination of is sup orting frame, a fixed shaft carried therefi a rotatable member mounted at one end on said fixed shaft and rotatable thereon and mounted at its-other end in a bushing which surrounds said rotatable member, means for rotating said member, an inclined shaft mountetlin said rotatable member and extendin through said bushing to a point beyondhe end of said rotatable member means for mounting the ball on the end of said shaft, afgear secured to the fixed shaft,

a gear secured to the inclined shaft and meshing with. the fixed gear whereby said rotatable member as it rotates causes the inclined shaft to rotate, means carried by the frame for suplportin the socket which is to be lapped wit said all, said inclined shaft and said rotatable member being so disposed relative to each other that their axes intersect in the center of the ball being lapped.

6. In a machine for lappin ball and socket joints, the combination 0 a supporting frame, a rotatable member, a fixed shaft carried b the frame and extending into one end of said rotatable member,' a bushing carried b the frame and surrounding the other end 0 said rotatable member whereby said member rotates on said shaft and in said bushing, an inclined shaft mounted in said rotatable member and extending through the bushing and beyond the end of said rotatable member, means for clamping the ball at the end of said shaft, a supporting bracket carried by the frame, on which the socket is mounted in which said ball is to be lapped. means whereby said rotatable member as it rotates, rotates the inclined shaft, the axis of said rotatable member and the axis of said inclined shaft intersecting in the center of the ball being lapped.

7. In a machine for lappin ball and socket joints, the combination 0 a supporting frame, a rotatable member, a fixed shaft carried b the frame and extending into one end of sand rotatable member, a bushing carried by the frame and surrounding the other end of said rotatable member whereby said member rotates on said shaft and in said bushing, an inclined shaft mounted in said rotatable member and extending through the bushing and beyond the end of said rotatable member, means for clamping the ball at the end of said shaft, a supporting bracket carried by the frame, on which the socketis mounted in which said ball is to be lapped, means whereby said rotatable member as it rotates, rotates the inclined shaft, the axis of said rotatable member and the axis of said inclined shaft intersecting in the cen- 8. In a machine for lapping ball andv socket joints, the combination of a support-' ing frame, a rotatable member, a fixed shaft carried b the frame and extending into one end of said rotatable member, a bushing carried by the frame and surrounding the other end of. said rotatable member whereby said member rotates on saidshaft and in said bushin an inclined shaft mounted in said rot-atab e member and extending through the bushing and beyond the end of said rotatable znember, means for clamping the ball at the end of said shaft, a supporting bracket carried by the frame, on which the socket is mounted in which said ball is to be lapped, means whereby said rotatable member as it rotates, rotates the inclined shaft, the axis of said rotatable member and the axis of said inclined shaft intersecting in the center of the ball being lapped, means for pivotally supporting the bracket carrying the socket member, and an adjustable stop carried by said bracket for positioning the same relative to the rotatable member. I

In testimony whereof, I-affix my signature.

ARVID ERIOSSON. 

